Photoshop unable to save files december 09 2020

For your saving issue, providing a few extra details can help with suggested solutions:

• Does the error appear with every file type or just one? (For example only with PSDs not JPGs)
• Where are you saving the files (local hard drive, network, external drive)?
• What's your Operating System?

For the preference issue, try reset your preferences. Here is a page on how to do that:
https://www.photoshopessentials.com/basics/reset-photoshop-preferences/ 

I've been having this all day on big photoshop files. Also I can turn layers off and they go off, and then back on and they stay off. Whatever @Adobe have done in this latest update, they need to undo, because they have made my Mac incredibly buggy. Not impressed when I've got work to do. It's laggy, I have poor performance doing basic things. This is a 2019 Mac Pro 16 core with the pro vega GPU with 32gb ram. Should not have these issues. When are Adobe going to adequately support this Mac.